LTB Weather + Wireless

thingiverse

This project builds upon the previously published Weather Station design (https://www.thingiverse.com/thing:2849562), released in March 2018. The sensors and electronics have been rearranged, and a 433MHz wireless connection now links remote sensors to the receiving console. Weather data can be displayed in several ways, including on an LCD screen (20x4), printed serially to the Arduino IDE terminal, or sent as a CSV string to a Raspberry Pi for database and graphing display. A demo video showcasing the printed parts and electronics in action is available at https://youtu.be/bPasvq7NFdE. The wireless design employs a 433MHz transmitter/receiver combo and utilizes Manchester protocol to send packets. This is detailed in the Arduino source code, which uses mono-spaced typeface for easier readability. The algorithm decoding the Manchester format has been significantly revamped, making it simpler to understand and repurpose. The Arduino programs are concise and should serve as a good starting point for builders with medium-level skills. For the 3-D printer parts and demo Arduino Uno setup, refer to my Thingiverse project at https://www.thingiverse.com/thing:2849562. For more information on Manchester protocol, visit my GitHub site at https://github.com/robwlakes/ArduinoWeatherOS. To see an example of what can be done with a Raspberry Pi and CSV weather data, check out my website at http://www.laketyersbeach.net.au/weather.html (note that this site uses commercial sensors from Oregon Scientific, but does utilize an Arduino to feed CSV files to the RPi from intercepted 433Mh signals). I have attempted to calibrate the rain gauge, but the anemometer remains uncalibrated. When I acquire the necessary equipment, I will publish a conversion factor. Until then, the transmitter simply transmits the number of 'clicks' the rain gauge and anemometer make, making it best to apply a conversion factor in the receiver console. The temperature data has been deliberately reduced in precision, using one byte to store the outside temperature with an offset of +20 added to accommodate negative temperatures. Using a DHT22 sensor for temperature and humidity will improve accuracy and may warrant sending more accurate temperature readings. While 433MHz is considered "old school" today, it remains a robust and economical choice. I leave it up to others to add more sophisticated interfaces like LoRA, BT, or WiFi.